Symmetrical and asymmetrical disazo dyestuffs



3,526,618 SYMMETRICAL AND ASYMMETRICAL DISAZO DYESTUFFS Walter Horstmann, Cologne-Buchheim, and Edgar Siege],

Leverkusen-Steinbuechel, Germany, assignors to Farbenfabriken Bayer Aktiengesellschaft, Leverkusen, Germany, a corporation of Germany No Drawing. Filed May 15, 1967, Ser. No. 638,649 Claims priority, applicatioggermany, May 23, 1966,

Int. Cl. c691 43/00 US. Cl. 260-152 8 Claims ABSTRACT OF THE DISCLOSURE Azo dyestuffs which are free of sulphonic acid have the formula:

wherein B is a divalent arylene amide, Y is oxygen or NR, X represents a ring substituent, and m is 03. Such dyestuifs are characterized by good fastness to solvents, light and migration, and by good thermal stability, and are useful for dyeing synthetic materials and for the production of printing colors and pigment pastes.

The object of the present invention comprises valuable new azo dyestuffs which are free from sulphonic acid groups and correspond to the general formula United States Patent Office 3,526,618 Patented Sept. 1, 1970 and ethoxy; fiuoro, bromo, methylsulphonyl, phenylsulphonyl, trifluoromethyl substituents; and carbalkoxy substituents, such as carbomethoxy and carbethoxy.

Suitable bivalent organic radicals B are, for example: N,N'-arylene-bis-[2 hydroxy naphthoyl (3')]-amides, N,N-arylene-bis-acetoacetyl-amides, arylene-bis-[3-meth ylpyrazolone =(5) yl (1)] or arylenewbis-[3-methyl-5- amino-pyrazolyl-(1)] of the formula NH: H2N I /NAr-N CH CH:

The following radicals may be mentioned for R, for example: hydrogen; methyl, ethyl, phenyl radicals; substituted phenyl radicals, such as 2- or 3- or 4-chloro-, 2- or 3- or 4-methyl-, 2- or 3- or 4-methoxy-phenyl radicals; cyclohexyl, naphthyl-(l) or -(2), pyridy1-(2) or benzothiazolyl radicals.

The new disazo pigments of the Formula I are obtained by converting disazo dyestuffs of the formula H000 OOOH X)m (X in (II) in which B, X and m have the same meaning as above, with dehydrating agents into the dianhydrides, or by condensing the tetracanboxylic acids of the Formula II or their di-anhydrides with at least 2 moles of a compound of the formula in which R has the same meaning as above, to form the di-imide compound, selecting starting components which are free from sulphonic acid groups. In this way there are obtained pigment dyestuffs which are sparingly soluble in organic solvents.

The starting dyestuffs of the Formula II can be obtained by coupling 1 mole of a bifunctional coupling component H--B-H with 2 moles of diazotised, identical or different, optionally substituted amino-phthalic acid, choosing starting components which are free from sulphonic acid groups. The coupling of, initially, one mole of diazotised, optionally substituted amino-phthalic acid 'With one of the bivalent organic radicals mentioned above leads to a monoazo dyestuif which is readily soluble in an alkaline medium, due to the two carboxyl groups, so that the reaction with another mole of optionally substituted aminophthalic acid can easily be performed. Some of the resultant disazo-tetracarboxylic acid dyestufis are readily soluble in the reaction medium, others are more sparingly soluble.

The following diazo components can be used for synthetising the disazo dyestufis (H), for example: 3-aminophthalic acid, 3-amino-4-methyl-phthalic acid, 3-amino-6- methyl-phthalic acid, 3-amino-5-nitro-phthalic acid, 4- amino-fi-nitro-phthalic acid, 3-amino-4-methoxy-phthalic acid, 3-amino-6-mJethoxy-phthalic acid, 3-amino-4-chlorophthalic acid, 3-amino-6-chloro-phthalic acid, 3-amino-5, 6-dimethoxy-phthalic acid, 3-amino-6-fluoro-phthalic acid, 3-amino-6-bromo-phthalic acid, 3 amino 6 phenylsulphonyl-phthalic acid, 4-amino-phthalic acid, 4-amino-3- chloro-phthalic acid, 4-amino-5-chloro-phthalic acid, 4- amino-3-methyl-phthalic acid, 4-amino-5-methyl-phtha1ic acid, 4-amino-3-methoxy-phthalic acid, 4 aminomethoxy-phthalic acid, 4-amino-5,6-dichloro-phthalic acid, 4- amjno-3,6-dichloro-phthalic acid, 4-amino 5 methylsulphonyl-phthalic acid, 4-amino-5-phenylsulphonyl-phthalic acid.

Examples of suitable coupling components H-B-H are the following:

N,N'-bis- [3 '-'hydroxy-naphthoyl- (2') ]-phenylenediamine-1,4,

phenylene-diamine-l ,4,

N,N'-bis- [3 '-hydroxy-naphthoyl- 2') -2-methy1- phenylene-diarnine-1,4,

N,N'-bis- [3 '-hydroxy-naphthoyl- (2') ]-4",4"'-diaminodiphenyl,

N,N-bis- [3 -hydroxy-naphthoyl- (2) ]-3",3 "'-dichlor0- 4",4"'-diamino-diphenyl,

N,N'-bis- 3-hydroxy-naphthoyl- (2') -3,3"'-dimethoxy- 4",4-diamino-dipheny1,

N,N'-bis- [3'-hydroxy-naphthoyl- (2') ]-3",3"-dimethyl- 4",4" '-diamino-diphenyl,

N,N'-bis- 3-hydroxy-naphthoyl- (2) ]-4",4'-diaminodiphenyl-methane,

N,N'-bis- [3 '-hydroxy-naphthoyl- (2' -4",4'-diaminodiphenyl ether,

N,N'-bis-[3 '-hydroxy-naphthoyl- (2' ]-4,4-diaminodiphenyl-sulphone,

N,N'- bis-[3 '-hydroxy-naphthoyl-( 2' ]-4",4"'- diaminobenzophenone,

N,N'-bis-[3 '-hydroxy-naphthoyl- (2' ]-pheny1 enediamine-1,3,

N,N'-bis- [3 '-hydroxy-naphthoyl- (2' ]-2-methylphenylene-diamine- 1 ,3

N,N-bis-[3 '-hydroxy-naphthoyl- (2 ]-2,5-dimethylphenylene-diamine-1,4,

N,N-bis [3 -hydroxy-naphthoyl- (2') ]-4,4"'-diaminostilbene,

N,N-bis- 3-hydroxy-naphthoyl- (2') ]-4,4"'-diaminodiphenyl-urea,

N,N-bis- 3-hydroxy-naphthoyl- (2') -2,7-diaminonaphthalene,

N,N'-bis- 3 -hydroxy-naphthoyl- 2') ]-2,7-diaminodiphenylene-oxide,

N,N'-bis-(acetoacetyl)-phenylene-diamine1,4,

N,N-bis-(acetoacetyl -2,5-dichloro-phenylenediamine-1,4,

N,N-bisacetoacetyl) -2,5-dimethyl-pheny1enediamine-1,4,

N,N'-bisaceto acetyl) -2-chloro-phenylenediamine-l ,4,

N,N-bisacetoacetyl) -2-methyl-phenylenediamine-1,4,

N,N-bis- (acetoacetyl) -biphenylene-4,4-diamine,

N,N'-bis- (acetoacetyl) -2,2'-dichloro-biphenylene- 4,4-diamine,

N,N-bis- (acetoacetyl -3,3 '-dichloro-biphenylene- 4,4-diamine,

N,N-bisacetoacetyl) -3 ,3'-dimethyl-biphenylene- 4,4-diamine,

N,N'-bis-(acetoacety1) -4,4'-diamino-diphenylmethane,

N,N-bisacetoacetyl) -4,4'-diamino-dip-henylsulphone,

N,N-bis- (acetoacetyl) -4,4'-diamino-diphenyl ether,

N,N-bis- (2'-hydroxy-benzoyl- -phenylenediamine-1,4,

Phenylene-( 1,4) -bis- [3 -methyl-pyrazolon (5 y 1' a I Phenylene-( 1,4 -bis- 3 '-carbomethoxy-pyrazolon- 5' Phenylene-(1,4)-bis-[3'-methyl-5-amino-pyrazol- Biphenylene- 4,4 -bis- 3"-methyl-5 "-amino-pyrazol- Biphenylene- (4,4 -bis- [3" methyl-pyrazolon- (5" Biphenylene- (4,4 -bis- 3 "-carbomethoxy- -amino- Py -y 1,

[3,3-dimethyl-biphenylene- (4,4) -bis- [3 "-methylpyrazolon- (5" -yl-( 1") [3,3'-dimethyl-biphenylene- (4,4) ]-bis- 3"-methyl- 5"-amino-pyrazol-yl-(1") The disazo-tetracarboxylic acids (II) which are comparatively readily soluble in water are converted according to the invention by treatment with dehydrating agents, for example, by heating with acetic acid, acetic anhydride, sodium acetate or iron (III) chloride, by themselves or in a high-boiling organic solvent, into the corresponding disaZo-tetra-carboxylic dianhydride (I) (Y=O), which are sparingly soluble in water and in organic solvents.

Condensation of the starting components (II) or their di-anhydrides with ammonia or amines (III) is preferably carried out in a high-boiling organic solvent and in the presence of dehydrating agents; the components may also serve themselves as organic solvents. For example, the condensation is carried out at an elevated temperature, generally in the range from C. to 240 C., preferably between C. and 180 C., and, if desired, under pressure. Monoamines suitable for this reaction are, for example: methylamine, ethylamine, aniline, 2- or 3- or 4-chloro-aniline, 2- or 3- or 4-methyl-aniline, 2- or 3- or 4-methoxy-aniline, 2- or 4-nitroaniline, 4-amino-benzamide, N-acetyl-phenylene-diamine-1,4, N-benzoyl-phenylene-diamine 1,3 cyclohexylamine, Z-aminobenzothiazole, Z-amino-pyridine, 1- and Z-amino-naphthalene and 3-amino-4-chloro-benzamide.

The following solvents boiling above 80 C. are suitable, for example, for the condensation of the disazo dyestufis (II) or their di-anhydrides with the compounds (III) in high-boiling organic solvents: benzene, toluene, xylenes, chlorobenzene, 0-, m-, p-dichlorobenzene, trichlorobenzenes, quinoline, nitrobenzene, glacial acetic acids, cyclohexane, 1,2,3,4-tetrahydronaphthalene, naphthalene, tetrachloroethylene, anisole, diphenyl ether, di-nbutyl ether, decalin, and mixtures of solvents of this type. Dehydrating agents which are preferably used are, for example: formic acid, acetic acid, propionic acid, anhydrous sodium acetate, zinc chloride, iron chloride, aluminum chloride and boron trifluoride.

For the reaction of the disazo-tetracarboxylic acids (II) or their di-anhydrides with the compounds (III) there are used at least 2 moles of the compounds (III); in general, the operation is carried out with an excess of up to 5 moles of the component (III) per mole of the component (H), in order to achieve a complete conversion of the components (II).

Symmetrical or asymmetrical disazo dyestuffs of the Formula I can be synthetised, depending upon the choice of the components (III).

The products which can be obtained according to the present process are valuable pigment dyestuffs which are generally characterised by good fastness to solvents, light and migration and by a good thermal stability. They are used for colouring synthetic materials, such as plasticisercontaining polyvinyl chloride, polyethylene and acryloni- 410 parts of a 10% sodium hydroxide solution and 1000 trile-butadiene-styrene copolymers and graft polymers, parts of ice are added and the above diazo suspension is lacquers, papers, and for the production of printing introduced at -10 in the presence of an emulsifier. colours and pigment pastes. The mixture is stirred at room temperature for a further In the following examples the parts are parts by weight; 2 hours, then adjusted to pH 1-2 by means of semi-conthe temperatures are degrees centigrade. 5 centrated hydrochloric acid, the dyestuif is filtered off EXAMPLE 1 with suction, washed with water until neutral and dried at 80 until the weight is constant. The yield is 91 parts.

Parts 3-amillo'phthallc acld e suspended 1I1 500 The dyestuif is converted into the di-anhydride by heat- Pafts of Water, 200 Parts of ice and 31 Parts Of COHCBII- ing it with 500 parts chlorobenzeneand 50 parts acetic trated hydrochloric acid are added and the mixture is anhydride at about 120 f 3 hours 84 Parts f the diazotised at 0-5 with a solution of 17.2 parts sodium h d -id are b i d,

nitrite in 50 parts of water. 8.0 parts of the di-anhydride are suspended in 500 34 Parts y )-P Y parts o-dichlorobenzene, 5 parts aniline are added and are Suspe in 1 Parts ethanol, a solutlon 0f 80 Parts the mixture is heated at 120 for 4 hours. 50 parts acetic sodium Carb i 2000 Parts Of Water is added and acid subsequently added and the mixture is kept at 120 the above diazo suspension is introduced at 10. When 130 f a further, 6-3 h Th pigment d t ff i the Coupling is completed, the dyestufi is filtered Off With filtered off with suction at 80, washed with warm 0- suction, washed with a little ice-water and dried at 60 dichlorobenzene until the runnings are clear and then until the weight is constant. dried until the weight is constant. The yield is 8.5 parts The dried and powdered dyestulf is heated in 500 parts of a pigment dyestufi of the formula chlorobenzene with 50 parts acetic anhydride at 100 for The product has very good fastness to light, lacquer 2 hours, then filtered oif with suction at room temperatum Washed with light petrol and dried. The yield is 71 coating and m1grat1on. It 1s suitable for colourmg acrylo parts disazo-tetracarboxylic di-anhydride of the formula nitrile-butadiene-styrene copolymers and graft polymers.

OOCHa NaCOC QN=NH (Lo O-NH-Q-NH-O o-dH-N=NQ The pigment has good fastness to light and lacquer coating. EXAMPLE 4 70 f th it d f 2 1 8.75 parts of the disazo dyestuff obtained from 2 parts 0 e azo yes 0 ame rom mo es of diazotised 4-amino-phthalic anhydride and N,N'-bisi f 3 f Phthahc anhydrflde ff (acetoacetyl)-2,5-dichlorophenylene-diamine-1,4 are first bls heated in 250 parts chlorobenzene with 2 parts methylammo-dlphenyl are heated m 500 parts chlorobenzene amine at 100 for 2 hours. 25 parts of glacial ace with 5 parts o-toluidine at 120 for 2 hours. 30 parts aclfd g; x g i g g ffi g h g of glacial acetic acid are then added and the mixture is a ur er ours. er c g a filtered off with suction, washed with chlorobenzene at kept at 130 fimher preclpltated Plg and dried at until the weight is constant 72 ment dyestutf 1s filtered off with suctlon at 7080,washed parts of the azo dyestuff of the formula with warm chlorobenzene until the runnings are clear are obtained. Y and dried in a vacuum at 80 until the weight is con- The pigment has very good fastness to migration and stant. 9.8 parts of a disazo pigment of the formula very good thermal stabili y. 7 -Q NH0C OH EXAMPLE 3 44.5 parts 3-amino-phtha1ic acid are suspended in 500 N=1TI parts of water, 200 parts of ice and 81 parts of concen- OH: trated hydrochloric acid are added and the mixture is diazotised at 0-5 with a solution of 17.2 parts sodium N- nitrite in 50 parts of water. The excess nitrite is destroyed by means of amidosulphonic acid.

55.0 parts N,N bis-[3'-hydroXy-naphthoyl-(2)-ami- 0 2 no]-phenylene-1,4 are suspended in 200 parts ethanol, are obtained.

The pigment has very good fastness to light and lacquer coatin 0.

' EXAMPLE 5 50 parts of the azo dyestutf obtained from 2 moles of diazotised 4-amino-5-chloro-phthalic acid and 1 mole N,N' bis (acetoacetyl)-2,5-dichlorophenylene-diarnine- 1,4 are converted into the dianhydride by heating for 2 hours in 500 parts chlorobenzene with 50 parts acetic anhydride.

7.6 parts of this di-anhydride are heated in 500 parts o-dichlorobenzene with 5 parts 2,5-dichloro-aniline at 120 for 2 hours. 50 parts of glacial acetic acid are then added and the mixture is kept at 130140 for a further 12 hours. The pigment is filtered off with suction at 70, washed with o-dichlorobenzene and dried in a vacuum at 80 until the weight is constant. The yield is 10.1 parts of the pigment dyestuif of the formula EXAMPLE 6 7.2 parts of the disazo dyestuff obtained from 2 moles of diazotised 3-amino-phthalic anhydride and 1 mole of the bifunctional coupling component are obtained.

Valuable pigment dyestuifs are also obtained when the process is carried out as described in the above examples, but using, instead of the diazo components, bifunctional coupling components and monoamines there specified, the

diazo components, coupling components and monoamines assembled in the following table:

Diazo component Coupling component Amine Shade 3-amino-phthalic acid N,N-bis-[3-hydroxy-naphthoyl-(2)]-pl1enyl- Methylamine Red.

ene-diamine1,4. d Benzylamine--. Red.

o-Toluidine 2,5-diehloro-an Cyclohexylamine o. -dicliloro-phenylene- Methylamine. Greenish yellow.

Do. Do. Do. fiTolui D0.

ethylannne Reddish yellow.

Anillne. Do. p-Toluidine Orange. N-b enzoyl-phenylene-diamine-l,4 D o. henylene-diamine-1,4. Aniline Yellow. Methyl'imin a D0, p-Toluidine Do,

, etoacetyl)-2,&dich1oro-phenylene- Aniline D5.

diamine-1,4.

do p-Toluidine Do. do N-acetyl-phonylene-diamine-l,4 Do. N ,N-bis-[3-hydroxy-naphthoyl- (2)]-phenyl- Methylamine ene-diamine-1,4.

d0 Aniline "do" p-Toluidine do p-Chloroaniline" Red. N,N-bis-[3-hydroxy-naphthoyl-(2)]-4,4- 2-amino-propane Red.

diamintrdiphenyl.

Do d0 Q-amino-pyridine Red.

. 4-amino-benzoic acid ethyl ester- Red p-Toluidine .11 Red:

Diazo component Coupling component Amine Shade 3-amino-6-chlorophthalic acid... N,N-bis-[3'-hydroxy-naphthoyl-(2)]-phenyl- Aniline Red.

enediamine-1,4.

Red. Red. Red. ,N-bis-[3-hydroxy-naphth (2')]-2-chloro Methylamin Red. phenylene-diamine-L-i. Do do Anilin Red. Do N ,N-bis-(acetoacetyl)-2,5-dich1oro-phenylene- 4-chloro-aniline Yellow diamine-1,4. 3-amino-(rehloro-phthalic acid .d Greenish yellow. 4-amino-5-chloro-phthalic acid... (10.. Do. 4-nmino-5,6-dich1oro-phthalic acid. d Do. B-aminc-G-chloro-phthalie acid [Plgenylf163;)?,4)]-bis-[3"-methyl-pyrazolon- Orange.

I, 4-ammo-5'chloro-phthalic acid ..do Do. Do [Phenylene-(4 4')]-bis-[3'-methyl5'-amino- 0,-To1u1dine Do.

pyrazolyl-l'i. Do do 2-chloroan1l1ne Do. Do [Bplgenlyerfi-(4,4!)1-bis-[3'-methyl-pi'yazolon- Aniline Do,

-y 3-amino-6-chloro-phthalic acid ..do 4 Aniline Do. 3-amino-phthalic acid N lf -b i s -(a c toacetyl)-2,5-dich1oro-phenylene- -chloroaniline Greenish yellow,

1am e- Do do 2,3-dimethyl-aniline Do. (in 3-chloro-aniline-. Do. (in m-Toluidine. Do. (in Z-methoxy-aniline. Do. (in 3-methoxy-aniline Do. do".-. 3,5-dichloro'aniline Do. Do ..do 3-methyl-4-ch1omaniline" Do, (in 3,5-dimethyLaniline Do. do 3,5-di-trifluoro-methyl-aniline-- Do. (In N-benzoyl-phenylene-diamine-L4 Do. Do N,N'-bis-(acetoacetyl)-2-chloro-5-methyl-phenyl- Cyclohexylamine Do.

, enediamine-l,4.

dn Methylamine Do. (in Aniline D0 fin o-Tnlniriinn (In Do N ,N-(acetoacetyl)-2,5-dimethy1-pheny1ener diam e-i,

yienediamine-1,4.

r'in (in N-bis-(acetoa Methylamine... diamine d0 Aniline D0 (in i m-Tnlnirlina Do (in Cyciohexylamine.-.. Do. do 4-chloro-aniline Do. Do.- do p-To1u1dine D fi-amino-5-methyl-phthalie MM do Cyclhexylamine D0. Do do Aniline D Do n Methylamine D 4-amino-5-methyl-phthalic acid Ng -bis-(a egtoacetyl)-2,5-dichloro-phenyleneni-Toluidine D0.

iamine- Do NaIEY-bis-[3-i1ydroxy-naphthoyl-(2)1-phenylene- Am Red.

am e-l,

D0 (in 4=ch1oro-aniline Red. Do ..do Cyclohexylamine- Red. 4-amino-5-ch1oro-phthaiic acid NaIIP-biS-(acZtoacetyl)-2,5-dichlorc-phenylene- Methylamiue Yellow.

, amine- Do n Cyclohexylamine Do. Do"-.- do m-Toluidine Do.

EXAMPLE 7 .7 ,.We c1a1m:

1. A dyestuif free from sulphonic acid groups and 28 parts of the disazo dyestuii obtained from 2 moles corregpondinfglto the formula of diazotised 3-amino-phthalic acid anhydride and 1 mole of N,N' bis (acetoacetyl) 2,5 dichlorophenylenediamine-1,4 and 16 parts of cycloheXylamine are heated for 4 hours at 130-140 in a mixture of 220 parts of 0- E dichloro-benzene and 30 parts of glacial acetic acid. The 1 Y pigment is filtered off with suction at -70 Washed with warm o-dichloro-benzene until the runnings are clear and 60 dried in a vacuum at 80? until the weight is constant. (mm 25.7 parts of a greenish yellow disazo pigment of the formula wherein B is the residue of N,N'-arylene-bis-[2-hydroxyare obtained. naphthoyl (3')] amide, N,N' arylene bis aceto- The pigment has very good fastness properties. acetyl amide, arylene bis [3 methyl pyrazolone- (5) yl (1)], arylene bis-[3 carbomethoxy pyrazolone (5) yl (1)], or arylene bis [3 methyl 5- amino-pyrazol-yl-( 1 )1 of the formula wherein the terms arylene and Ar denote phenylene, diphenylene, diphenylene methane, diphenylene ether, diphenylene sulphone, benzophenone, stilbene, diphenylene urea, naphthalene, diphenylene oxide, chlorinated phen- "ylene, chlorinated biphenylene, methyl phenylene, methyl biphenylene, or methoxy dipheuyleneyY is oxygen or NR, wherein R is hydrogen, hydroxyl, methyl, ethyl, propyl, phenyl, carbonamidophenyl, acetylamino phenyl, phenyl carbonylamino phenyl, cyclohexyl, benzothiazole, pyridine, naphthalene, chloro carbonamidophenyl, bi phenyl or pheuyl substituted by methyl, methoxy, nitro, chloro, carboethoxy or trifluoromethyl; X is lower alkyl,

lower alkoxy, halo, nitro, methyl sulphonyl, phenylsulphonyl, CF carbomethoxy or carboethoxy; and m is 0 to 3.

2. The azo dyestufi of the formula COCHs H3000 3. The azo dyestuff of the formula COCHa 4. The azo dyestuif of the formula Cl COCHB 1 Cl COCH:

HaC

6. The azo dyestufi' of the formula References Cited UNITED STATES PATENTS 3,182,073 5/1965 Lonerini 260152 XR 3,356,672 12/1967 Schefczik 260152 3,402,166 9/1968 Heckl et a1. 260152 3,415,806 12/1968 Pfister et a1. 260152 XR FOREIGN PATENTS 501,855 3/1939 Great Britain.

FLOYD D. HIGEL, Primary Examiner us. 01. X.R.

s-4, 7, 71; 106-288; 117 13s.s, 152; 260-37, 41, 41.5, 160, 176, 187, 310, 346.3, 518, 519, 560, 5 2

:33: of 2 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,526 ,6 8 Dated September 1, 1970 Walter Horstmann, et a1. Inventor(s) It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column Line Error HOOC should read UNITED STATES PATENT OFFICE Page 2 CERTIFICATE OF CORRECTION Patent 3,526 ,618 Dated September 1, 1970 Walter Horstmann, et a1. Inventor(s) It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

5-6 37-38 N COC -NH-OC-CH-N=N- should read H C0C 5 55-65 "-N=NNC" should read N=NHC 6 Example 4 "]-4"'-" should read ]-4",4"

12 Claim 3 "HCOC-" should read -HCCO formula J SIGNH) Aih 1L51 CSEAL) Attest:

Edward M. Fletcher, Ir. mm: B. 86mm, 38- 0mm flomisaioncr of Pateuts 

